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991.
The Paris agreement signed in April, 2016 aims to balance global anthropogenic carbon emissions and terrestrial carbon sinks by the middle of the 21st century. To fulfill this goal, it is necessary to calculate carbon fluxes of different regions reliably. The global carbon assimilation system is an effective technique for achieving this goal. The Ministry of Science and Technology of China supports the project entitled as study on the global carbon assimilation system based on multisource remote sensing data through the national key research and development programs for global change and adaptation during the thirteen-five period. This project will develop synergic inversion techniques for retrieving key parameters of biological and atmospheric cycles and for assimilating multisource remote sensing and ground based data. Then, the high resolution global carbon assimilation system coupled with an ecological model will be constructed. This system is able to assimilate jointly multisource observation data and to optimize key model parameters, photosynthesis and respiration carbon fluxes of global terrestrial ecosystems, and anthropogenic carbon emission fluxes of key regions. This system will be used to study quantitatively the spatial and temporal patterns of carbon fluxes of global terrestrial ecosystems and anthropogenic carbon emission fluxes of key regions and to identify the mechanisms driving the global terrestrial carbon sinks and sources. The outputs of this study will be helpful for the fulfillment of the key research and development programs for global change and adaptation and provide valuable data and technical support for the decision-making in China.  相似文献   
992.
Shanlianglishi Formation strata volcanic rocks are widely distributed in western fault zone of Kalamaili. Studies show that the rocks are basalt, andesite and basaltic andesite, calc-alkaline series with SiO2 content of samples ranging from 49.43% to 59.08%, TiO2 (1.18%~2.49%), P2O5 (0.21%~0.92%) and MgO (3.81%~6.28%). Samples have relatively high HFSE content (Ti, Zr, Y) and also high La/Nb (2.98~1.96), Zr/Y (9.36~4.01) ratio. The primitive mantle normalized trace element spider shows samples enriched LILE (Rb, Ba, K, U) and Pb, but relatively depleted Nb, Ta and Ti. Rare earth element distribution of REE shows slightly enriched LREE, (La/Yb)N=1.93~9.59, and that Eu is weakly negative anomaly (δEu=0.87~0.95). Combined with geochemical characteristics of WPB and VAB. Shanlianglishi Formation strata formed in the stretched after collision environmen. After partial melting of the enriched mantle that was previously metasomatized by the subduction fluid and with participation of the subduction sediment, magma experienced a certain degree of fractional crystallization and contamination by earth crust, and then erupted to form the Shanlianglishi Formation strata volcanic rocks. In eraly Late-Carboniferous, extensional movement was the most intense volcanic activity, which reached its peak in this area.  相似文献   
993.
To monitor environmental implications of cement dust on soil in industrial area, magnetic parameters and mineral compositions were measured by the samples of the cement dust, cement factory dustfall, cement, coal ash, topsoil of green space in the factory and topsoil outside the factory. Results showed that the major magnetic minerals in the samples were magnetite, the magnetic mineral particle size of cement dust, dustfall, cement and coal ash was coarse Multi-Domian (MD) and Pseudo-Single-Domain (PSD). As topsoil of green space in the factory and topsoil outside the factory were polluted by cement dust, their magnetic properties had been obviously changed; the concentration of magnetic minerals elevated and particle size became coarser. The magnetic parameters (χfdARM/χ,χARM/SIRM) value can reflect the pollution level of the soil, the lower its value was, the more serious soil was polluted. X-ray diffraction results showed that the mineral compositions of the topsoil of green space in the factory and topsoil outside the factory were quartz and calcite, which were the same as cement dust. Magnetic parameters combination characteristics of topsoil can monitor the soil environmental changes in cement industry area.  相似文献   
994.
Since the forest eco-hydrology of arid area shows a well sensitivity of the global climate change, the relationship between forest and water and the hydrological function has attracted the attention of academic communites and management departments. This paper expounds the research progress in arid mountain forest eco-hydrology, and analyses the formation and stable mechanism of forest patch pattern, the relationship between forest and water yield and the response of forest eco-hydrology to climate change from three aspects: Forest spatial pattern, hydrological process and its response to climate change. In addition, combined with the current research progress, the research emphases in the future are put forward: Strengthening the research on the coupling of vegetation pattern and hydrological process; solving the scale problem by using remote sensing technique and model; enhancing the understanding towards the hydrological function of forest; determining the suitable forest scale which can balance the relationship of ecology and hydrological effect.  相似文献   
995.
西藏雅鲁藏布江缝合带西段普兰纯橄岩中橄榄石存在透辉石和磁铁矿共生出溶现象。这类纯橄岩非常新鲜,主要由橄榄石、尖晶石和透辉石等矿物组成。橄榄石的Fo值是90.1~90.7,铬尖晶石的Cr~#为19.8~20.8,远小于蛇绿岩地幔橄榄岩中常见纯橄岩中铬尖晶石的铬值(Cr~#60)。基于前人研究结果,提出这种现象是由于亏损方辉橄榄岩与含钛、铝、钙熔体发生交代作用,从而形成橄榄石的固溶体存在Ti~(4+)、Al~(3+)、Ca~(2+)、Fe~(3+),而Cr~(3+)进入铬尖晶石结晶。后期由于岩体在抬升过程中降温,橄榄石中出溶形成单斜辉石和磁铁矿,而铬尖晶石结晶被保留。依据铬尖晶石-橄榄石的矿物化学成分,识别出低铬纯橄岩具有最低的部分熔融程度为~8%,Cr~#最高的纯橄岩壳其部分熔融程度达到~50%,表明不同岩相间其形成背景存在明显差异。因此,笔者认为普兰蛇绿岩具有多阶段的过程。首先是在洋中脊环境下经历富Ca、Al和Na等熔体交代和部分熔融作用,后受到俯冲带玻安质熔体改造。  相似文献   
996.
昭通国家级页岩气示范区黄金坝气田是继礁石坝和长宁—威远之后中国又一个在页岩气勘探、开发领域实现重大突破的地区,为了系统地展示黄金坝气田页岩气资源富集的储层条件,为未来的勘探工作提供参考,以五峰—龙马溪组页岩气储层为研究对象,从区域地质条件、储层岩石学、物性和地球化学4个方面对该页岩气储层进行了综合研究。结果表明稳定的区域构造和良好的顶底板条件是黄金坝地区页岩气资源富集的关键,良好的保存条件使储层维持了较高的压力(压力系数1);较高的孔隙度(平均4%)和TOC含量(目的层2%)提供了良好的储集空间,使储层具有较高的含气量(1.35~3.48 cm3/g,平均2.50 cm3/g);天然气地球化学数据表明,区内天然气主要成分为CH4(97%),其次还含有少量的C2H6、C3H8和CO2;天然气同位素数据表明烃类C同位素组成发生了倒转,表明储层具有良好的封闭性。但储层孔隙系统较为复杂,且非均质性极强,从而导致渗透率较低,在储层改造施工过程中应予以充分考虑。总体上,黄金坝气田具有较好的开发前景,生产测试表明,区内直井压裂产量为0.5×104~3.5×104m3/d/井,水平井压裂产量可达12×104~40×104m3/d/井。  相似文献   
997.
贵州矿产资源开发布局与优化探讨   总被引:1,自引:1,他引:0       下载免费PDF全文
曾芳  孙亚莉  江金进 《贵州地质》2016,33(2):148-154
在分析贵州矿产资源开发布局现状及存在问题的基础上,提出了贵州省矿产资源开发布局优化的原则,对开发区域布局和开发规划分区进行了探讨;调整了黔中、黔西、黔北、黔东四大矿产开发利用区域,划定禁止开采区、限制开采区、矿产资源重点矿区三类规划分区。  相似文献   
998.
点苍山-哀牢山变质杂岩带中北段嘎洒地区出露了多种典型的变沉积岩,其中夕线石榴黑云二长片麻岩和二云母片岩保存多期/多阶段矿物相转变特征,本文通过岩相学和矿物化学的综合分析,并结合传统矿物对温压计的估算结果,限定上述典型变沉积岩峰期角闪-麻粒岩相(M1)阶段、近等温减压-高温剪切变形阶段(M2)和晚期退变质(M3)阶段的矿物组合及变质温压条件。峰期角闪-麻粒岩相(M1)阶段的矿物组合为:石榴石(Grt)+板柱状夕线石(Sil1)+黑云母(Bt1)+钾长石(Kfs)+斜长石(Pl)+石英(Qtz)+钛铁矿(Ilm),变质温度压力条件为t=690~750℃,p=690~810 MPa;近等温减压-高温剪切变形阶段(M2)阶段,稳定矿物组合为:Grt+Sil2+Bt2+Kfs+Pl+Qtz+Ilm,黑云母在强烈走滑剪切作用下发生脱水熔融反应:2 Bt→Sil+6(Mg,Fe)O+K_2O+5 Qtz+2 H_2O,石榴石、黑云母和夕线石等受到剪切变形影响而发生强烈定向,形成的温度压力条件为t=650~720℃,p=450~630 MPa;晚期退变质阶段(M_3)的稳定矿物组合为:Qtz+Bt+Ms+Pl,退变的温度压力条件为t=580~640℃,p=400~500MPa。其变质演化p-T轨迹样式具有近等温减压的顺时针型式,表明点苍山-哀牢山变质杂岩带曾经历了一次明显的俯冲-碰撞造山事件,峰期变质可达到角闪-麻粒岩相;在碰撞后的构造折返过程中,上述变质岩石发生强烈的高温剪切变形作用,并伴随着黑云母等含水矿物的脱水熔融。  相似文献   
999.
通过对澜沧江杂岩带小黑江-上允地区蓝片岩的岩相学、地球化学、成因矿物学以及相平衡模拟的综合研究,阐述蓝片岩的原岩以及变质演化过程。地球化学分析结果显示,蓝片岩具有一致的稀土元素配分模式,具弱Eu正或负异常,稀土元素和微量元素特征与OIB相似,其原岩可能为OIB型玄武岩。详细矿物学研究表明,本区蓝片岩记录了俯冲峰期蓝片岩相变质和峰期后绿片岩相变质两个变质阶段,其矿物组合分别为蓝闪石+钠长石+多硅白云母+绿泥石+绿帘石和蓝闪石+钠长石±阳起石+绿泥石+绿帘石。通过Na_2O-Ca O-Fe O-MgO-Al_2O_3-SiO_2-H_2O-O体系相平衡计算,得到两个阶段的压力范围分别约为0.95 GPa和0.40 GPa。  相似文献   
1000.
武川高级片麻岩地体中石榴基性麻粒岩的变质用与同位素年代学研究对于揭示阴山陆块新太古代构造演化过程具有十分重要的研究意义。它们主要以不规则透镜体或变形岩墙/岩脉群的形式赋存于新太古代晚期英云闪长质片麻岩或变质表壳岩系之中,并切割近南-北向的区域性片麻理。岩相学观察、矿物相转变分析与矿物化学研究表明,武川石榴基性麻粒岩保留了十分典型的高压麻粒岩相矿物:石榴石+单斜辉石+斜长石+角闪石+石英+铁-钛氧化物。其中,粗粒石榴石边部常发育微弱的扩散环带,表现为从幔部至边部,镁铝榴石组分不断减少,相应地铁铝榴石组分不断增加,而钙铝榴石与锰铝榴石组分基本不变,指示晚期冷却降温作用对石榴石成分产生一定影响。斜长石具有细粒包体型与粗粒基质型两种不同的类型,它们具有十分相似化学成分,均为An=35~45的中长石。在NCFMASHTO(Na_2O-CaO-FeO-MgO-Al_2O_3-SiO_2-H_2O-TiO_2-Fe_2O_3)体系下,利用THERM OCA LC 3.33软件,对两件石榴基性麻粒岩样品进行了相平衡模拟,模拟的峰期矿物组合为:石榴石+单斜辉石+斜长石+角闪石+石英+铁-钛氧化物,与岩相学观察十分一致。采用石榴石中最小x(g)Fe~(2 +)/(Fe~(2 +)+Mg))与斜长石是中最小ca(pl)(Ca/(Ca+Na))等值线,将本区石榴基性麻粒岩峰期高压麻粒岩相的温压条件限定在P=1.31~1.40GPa,T=770~840℃的范围内。LA-ICP-MS锆石U-Pb定年结果表明,两件石榴基性麻粒岩麻粒岩中发育的变质锆石分别记录了2517±6Ma(BT58-1,MSWD=0.66,n=21)与2512±16Ma(LH66-1,MSWD=0.26,n=42)的加权平均年龄,与阴山陆块其它新太古代岩石记录的约2500Ma变质年龄一致,被解释为本区石榴基性麻粒岩遭受高压麻粒岩相变质时代。结合本区其它新的研究资料,本文认为武川石榴基性麻粒岩形成可能与区内新太古代晚期造山作用有关。  相似文献   
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